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  <div class="section" id="module-xml.dom">
<h1>20.6. <tt class="xref docutils literal"><span class="pre">xml.dom</span></tt> &#8212; The Document Object Model API<a class="headerlink" href="#module-xml.dom" title="Permalink to this headline">¶</a></h1>
<p>
<span class="versionmodified">New in version 2.0.</span></p>
<p>The Document Object Model, or &#8220;DOM,&#8221; is a cross-language API from the World Wide
Web Consortium (W3C) for accessing and modifying XML documents.  A DOM
implementation presents an XML document as a tree structure, or allows client
code to build such a structure from scratch.  It then gives access to the
structure through a set of objects which provided well-known interfaces.</p>
<p>The DOM is extremely useful for random-access applications.  SAX only allows you
a view of one bit of the document at a time.  If you are looking at one SAX
element, you have no access to another.  If you are looking at a text node, you
have no access to a containing element. When you write a SAX application, you
need to keep track of your program&#8217;s position in the document somewhere in your
own code.  SAX does not do it for you.  Also, if you need to look ahead in the
XML document, you are just out of luck.</p>
<p>Some applications are simply impossible in an event driven model with no access
to a tree.  Of course you could build some sort of tree yourself in SAX events,
but the DOM allows you to avoid writing that code.  The DOM is a standard tree
representation for XML data.</p>
<p>The Document Object Model is being defined by the W3C in stages, or &#8220;levels&#8221; in
their terminology.  The Python mapping of the API is substantially based on the
DOM Level 2 recommendation.</p>
<p>DOM applications typically start by parsing some XML into a DOM.  How this is
accomplished is not covered at all by DOM Level 1, and Level 2 provides only
limited improvements: There is a <tt class="xref docutils literal"><span class="pre">DOMImplementation</span></tt> object class which
provides access to <tt class="xref docutils literal"><span class="pre">Document</span></tt> creation methods, but no way to access an
XML reader/parser/Document builder in an implementation-independent way. There
is also no well-defined way to access these methods without an existing
<tt class="xref docutils literal"><span class="pre">Document</span></tt> object.  In Python, each DOM implementation will provide a
function <a title="xml.dom.getDOMImplementation" class="reference internal" href="#xml.dom.getDOMImplementation"><tt class="xref docutils literal"><span class="pre">getDOMImplementation()</span></tt></a>. DOM Level 3 adds a Load/Store
specification, which defines an interface to the reader, but this is not yet
available in the Python standard library.</p>
<p>Once you have a DOM document object, you can access the parts of your XML
document through its properties and methods.  These properties are defined in
the DOM specification; this portion of the reference manual describes the
interpretation of the specification in Python.</p>
<p>The specification provided by the W3C defines the DOM API for Java, ECMAScript,
and OMG IDL.  The Python mapping defined here is based in large part on the IDL
version of the specification, but strict compliance is not required (though
implementations are free to support the strict mapping from IDL).  See section
<a class="reference internal" href="#dom-conformance"><em>Conformance</em></a> for a detailed discussion of mapping requirements.</p>
<div class="admonition-see-also admonition seealso">
<p class="first admonition-title">See also</p>
<dl class="last docutils">
<dt><a class="reference external" href="http://www.w3.org/TR/DOM-Level-2-Core/">Document Object Model (DOM) Level 2 Specification</a></dt>
<dd>The W3C recommendation upon which the Python DOM API is based.</dd>
<dt><a class="reference external" href="http://www.w3.org/TR/REC-DOM-Level-1/">Document Object Model (DOM) Level 1 Specification</a></dt>
<dd>The W3C recommendation for the DOM supported by <a title="Lightweight Document Object Model (DOM) implementation." class="reference external" href="xml.dom.minidom.html#module-xml.dom.minidom"><tt class="xref docutils literal"><span class="pre">xml.dom.minidom</span></tt></a>.</dd>
<dt><a class="reference external" href="http://www.omg.org/docs/formal/02-11-05.pdf">Python Language Mapping Specification</a></dt>
<dd>This specifies the mapping from OMG IDL to Python.</dd>
</dl>
</div>
<div class="section" id="module-contents">
<h2>20.6.1. Module Contents<a class="headerlink" href="#module-contents" title="Permalink to this headline">¶</a></h2>
<p>The <tt class="xref docutils literal"><span class="pre">xml.dom</span></tt> contains the following functions:</p>
<dl class="function">
<dt id="xml.dom.registerDOMImplementation">
<tt class="descclassname">xml.dom.</tt><tt class="descname">registerDOMImplementation</tt><big>(</big><em>name</em>, <em>factory</em><big>)</big><a class="headerlink" href="#xml.dom.registerDOMImplementation" title="Permalink to this definition">¶</a></dt>
<dd>Register the <em>factory</em> function with the name <em>name</em>.  The factory function
should return an object which implements the <tt class="xref docutils literal"><span class="pre">DOMImplementation</span></tt>
interface.  The factory function can return the same object every time, or a new
one for each call, as appropriate for the specific implementation (e.g. if that
implementation supports some customization).</dd></dl>

<dl class="function">
<dt id="xml.dom.getDOMImplementation">
<tt class="descclassname">xml.dom.</tt><tt class="descname">getDOMImplementation</tt><big>(</big><span class="optional">[</span><em>name</em><span class="optional">[</span>, <em>features</em><span class="optional">]</span><span class="optional">]</span><big>)</big><a class="headerlink" href="#xml.dom.getDOMImplementation" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a suitable DOM implementation. The <em>name</em> is either well-known, the
module name of a DOM implementation, or <tt class="xref docutils literal"><span class="pre">None</span></tt>. If it is not <tt class="xref docutils literal"><span class="pre">None</span></tt>, imports
the corresponding module and returns a <tt class="xref docutils literal"><span class="pre">DOMImplementation</span></tt> object if the
import succeeds.  If no name is given, and if the environment variable
<span class="target" id="index-741"></span><strong class="xref">PYTHON_DOM</strong> is set, this variable is used to find the implementation.</p>
<p>If name is not given, this examines the available implementations to find one
with the required feature set.  If no implementation can be found, raise an
<a title="exceptions.ImportError" class="reference external" href="exceptions.html#exceptions.ImportError"><tt class="xref docutils literal"><span class="pre">ImportError</span></tt></a>.  The features list must be a sequence of <tt class="docutils literal"><span class="pre">(feature,</span>
<span class="pre">version)</span></tt> pairs which are passed to the <tt class="xref docutils literal"><span class="pre">hasFeature()</span></tt> method on available
<tt class="xref docutils literal"><span class="pre">DOMImplementation</span></tt> objects.</p>
</dd></dl>

<p>Some convenience constants are also provided:</p>
<dl class="data">
<dt id="xml.dom.EMPTY_NAMESPACE">
<tt class="descclassname">xml.dom.</tt><tt class="descname">EMPTY_NAMESPACE</tt><a class="headerlink" href="#xml.dom.EMPTY_NAMESPACE" title="Permalink to this definition">¶</a></dt>
<dd><p>The value used to indicate that no namespace is associated with a node in the
DOM.  This is typically found as the <tt class="xref docutils literal"><span class="pre">namespaceURI</span></tt> of a node, or used as
the <em>namespaceURI</em> parameter to a namespaces-specific method.</p>
<p>
<span class="versionmodified">New in version 2.2.</span></p>
</dd></dl>

<dl class="data">
<dt id="xml.dom.XML_NAMESPACE">
<tt class="descclassname">xml.dom.</tt><tt class="descname">XML_NAMESPACE</tt><a class="headerlink" href="#xml.dom.XML_NAMESPACE" title="Permalink to this definition">¶</a></dt>
<dd><p>The namespace URI associated with the reserved prefix <tt class="docutils literal"><span class="pre">xml</span></tt>, as defined by
<a class="reference external" href="http://www.w3.org/TR/REC-xml-names/">Namespaces in XML</a> (section 4).</p>
<p>
<span class="versionmodified">New in version 2.2.</span></p>
</dd></dl>

<dl class="data">
<dt id="xml.dom.XMLNS_NAMESPACE">
<tt class="descclassname">xml.dom.</tt><tt class="descname">XMLNS_NAMESPACE</tt><a class="headerlink" href="#xml.dom.XMLNS_NAMESPACE" title="Permalink to this definition">¶</a></dt>
<dd><p>The namespace URI for namespace declarations, as defined by <a class="reference external" href="http://www.w3.org/TR/DOM-Level-2-Core/core.html">Document Object
Model (DOM) Level 2 Core Specification</a> (section 1.1.8).</p>
<p>
<span class="versionmodified">New in version 2.2.</span></p>
</dd></dl>

<dl class="data">
<dt id="xml.dom.XHTML_NAMESPACE">
<tt class="descclassname">xml.dom.</tt><tt class="descname">XHTML_NAMESPACE</tt><a class="headerlink" href="#xml.dom.XHTML_NAMESPACE" title="Permalink to this definition">¶</a></dt>
<dd><p>The URI of the XHTML namespace as defined by <a class="reference external" href="http://www.w3.org/TR/xhtml1/">XHTML 1.0: The Extensible
HyperText Markup Language</a> (section 3.1.1).</p>
<p>
<span class="versionmodified">New in version 2.2.</span></p>
</dd></dl>

<p>In addition, <tt class="xref docutils literal"><span class="pre">xml.dom</span></tt> contains a base <tt class="xref docutils literal"><span class="pre">Node</span></tt> class and the DOM
exception classes.  The <tt class="xref docutils literal"><span class="pre">Node</span></tt> class provided by this module does not
implement any of the methods or attributes defined by the DOM specification;
concrete DOM implementations must provide those.  The <tt class="xref docutils literal"><span class="pre">Node</span></tt> class
provided as part of this module does provide the constants used for the
<tt class="xref docutils literal"><span class="pre">nodeType</span></tt> attribute on concrete <tt class="xref docutils literal"><span class="pre">Node</span></tt> objects; they are located
within the class rather than at the module level to conform with the DOM
specifications.</p>
</div>
<div class="section" id="objects-in-the-dom">
<span id="dom-objects"></span><h2>20.6.2. Objects in the DOM<a class="headerlink" href="#objects-in-the-dom" title="Permalink to this headline">¶</a></h2>
<p>The definitive documentation for the DOM is the DOM specification from the W3C.</p>
<p>Note that DOM attributes may also be manipulated as nodes instead of as simple
strings.  It is fairly rare that you must do this, however, so this usage is not
yet documented.</p>
<table border="1" class="docutils">
<colgroup>
<col width="32%" />
<col width="35%" />
<col width="33%" />
</colgroup>
<thead valign="bottom">
<tr><th class="head">Interface</th>
<th class="head">Section</th>
<th class="head">Purpose</th>
</tr>
</thead>
<tbody valign="top">
<tr><td><tt class="xref docutils literal"><span class="pre">DOMImplementation</span></tt></td>
<td><a class="reference internal" href="#dom-implementation-objects"><em>DOMImplementation Objects</em></a></td>
<td>Interface to the underlying
implementation.</td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">Node</span></tt></td>
<td><a class="reference internal" href="#dom-node-objects"><em>Node Objects</em></a></td>
<td>Base interface for most objects
in a document.</td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">NodeList</span></tt></td>
<td><a class="reference internal" href="#dom-nodelist-objects"><em>NodeList Objects</em></a></td>
<td>Interface for a sequence of
nodes.</td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">DocumentType</span></tt></td>
<td><a class="reference internal" href="#dom-documenttype-objects"><em>DocumentType Objects</em></a></td>
<td>Information about the
declarations needed to process
a document.</td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">Document</span></tt></td>
<td><a class="reference internal" href="#dom-document-objects"><em>Document Objects</em></a></td>
<td>Object which represents an
entire document.</td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">Element</span></tt></td>
<td><a class="reference internal" href="#dom-element-objects"><em>Element Objects</em></a></td>
<td>Element nodes in the document
hierarchy.</td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">Attr</span></tt></td>
<td><a class="reference internal" href="#dom-attr-objects"><em>Attr Objects</em></a></td>
<td>Attribute value nodes on
element nodes.</td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">Comment</span></tt></td>
<td><a class="reference internal" href="#dom-comment-objects"><em>Comment Objects</em></a></td>
<td>Representation of comments in
the source document.</td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">Text</span></tt></td>
<td><a class="reference internal" href="#dom-text-objects"><em>Text and CDATASection Objects</em></a></td>
<td>Nodes containing textual
content from the document.</td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">ProcessingInstruction</span></tt></td>
<td><a class="reference internal" href="#dom-pi-objects"><em>ProcessingInstruction Objects</em></a></td>
<td>Processing instruction
representation.</td>
</tr>
</tbody>
</table>
<p>An additional section describes the exceptions defined for working with the DOM
in Python.</p>
<div class="section" id="domimplementation-objects">
<span id="dom-implementation-objects"></span><h3>20.6.2.1. DOMImplementation Objects<a class="headerlink" href="#domimplementation-objects" title="Permalink to this headline">¶</a></h3>
<p>The <tt class="xref docutils literal"><span class="pre">DOMImplementation</span></tt> interface provides a way for applications to
determine the availability of particular features in the DOM they are using.
DOM Level 2 added the ability to create new <tt class="xref docutils literal"><span class="pre">Document</span></tt> and
<tt class="xref docutils literal"><span class="pre">DocumentType</span></tt> objects using the <tt class="xref docutils literal"><span class="pre">DOMImplementation</span></tt> as well.</p>
<dl class="method">
<dt id="xml.dom.DOMImplementation.hasFeature">
<tt class="descclassname">DOMImplementation.</tt><tt class="descname">hasFeature</tt><big>(</big><em>feature</em>, <em>version</em><big>)</big><a class="headerlink" href="#xml.dom.DOMImplementation.hasFeature" title="Permalink to this definition">¶</a></dt>
<dd>Return true if the feature identified by the pair of strings <em>feature</em> and
<em>version</em> is implemented.</dd></dl>

<dl class="method">
<dt id="xml.dom.DOMImplementation.createDocument">
<tt class="descclassname">DOMImplementation.</tt><tt class="descname">createDocument</tt><big>(</big><em>namespaceUri</em>, <em>qualifiedName</em>, <em>doctype</em><big>)</big><a class="headerlink" href="#xml.dom.DOMImplementation.createDocument" title="Permalink to this definition">¶</a></dt>
<dd>Return a new <tt class="xref docutils literal"><span class="pre">Document</span></tt> object (the root of the DOM), with a child
<tt class="xref docutils literal"><span class="pre">Element</span></tt> object having the given <em>namespaceUri</em> and <em>qualifiedName</em>. The
<em>doctype</em> must be a <tt class="xref docutils literal"><span class="pre">DocumentType</span></tt> object created by
<a title="xml.dom.DOMImplementation.createDocumentType" class="reference internal" href="#xml.dom.DOMImplementation.createDocumentType"><tt class="xref docutils literal"><span class="pre">createDocumentType()</span></tt></a>, or <tt class="xref docutils literal"><span class="pre">None</span></tt>. In the Python DOM API, the first two
arguments can also be <tt class="xref docutils literal"><span class="pre">None</span></tt> in order to indicate that no <tt class="xref docutils literal"><span class="pre">Element</span></tt>
child is to be created.</dd></dl>

<dl class="method">
<dt id="xml.dom.DOMImplementation.createDocumentType">
<tt class="descclassname">DOMImplementation.</tt><tt class="descname">createDocumentType</tt><big>(</big><em>qualifiedName</em>, <em>publicId</em>, <em>systemId</em><big>)</big><a class="headerlink" href="#xml.dom.DOMImplementation.createDocumentType" title="Permalink to this definition">¶</a></dt>
<dd>Return a new <tt class="xref docutils literal"><span class="pre">DocumentType</span></tt> object that encapsulates the given
<em>qualifiedName</em>, <em>publicId</em>, and <em>systemId</em> strings, representing the
information contained in an XML document type declaration.</dd></dl>

</div>
<div class="section" id="node-objects">
<span id="dom-node-objects"></span><h3>20.6.2.2. Node Objects<a class="headerlink" href="#node-objects" title="Permalink to this headline">¶</a></h3>
<p>All of the components of an XML document are subclasses of <tt class="xref docutils literal"><span class="pre">Node</span></tt>.</p>
<dl class="attribute">
<dt id="xml.dom.Node.nodeType">
<tt class="descclassname">Node.</tt><tt class="descname">nodeType</tt><a class="headerlink" href="#xml.dom.Node.nodeType" title="Permalink to this definition">¶</a></dt>
<dd>An integer representing the node type.  Symbolic constants for the types are on
the <tt class="xref docutils literal"><span class="pre">Node</span></tt> object: <tt class="xref docutils literal"><span class="pre">ELEMENT_NODE</span></tt>, <tt class="xref docutils literal"><span class="pre">ATTRIBUTE_NODE</span></tt>,
<tt class="xref docutils literal"><span class="pre">TEXT_NODE</span></tt>, <tt class="xref docutils literal"><span class="pre">CDATA_SECTION_NODE</span></tt>, <tt class="xref docutils literal"><span class="pre">ENTITY_NODE</span></tt>,
<tt class="xref docutils literal"><span class="pre">PROCESSING_INSTRUCTION_NODE</span></tt>, <tt class="xref docutils literal"><span class="pre">COMMENT_NODE</span></tt>,
<tt class="xref docutils literal"><span class="pre">DOCUMENT_NODE</span></tt>, <tt class="xref docutils literal"><span class="pre">DOCUMENT_TYPE_NODE</span></tt>, <tt class="xref docutils literal"><span class="pre">NOTATION_NODE</span></tt>.
This is a read-only attribute.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.Node.parentNode">
<tt class="descclassname">Node.</tt><tt class="descname">parentNode</tt><a class="headerlink" href="#xml.dom.Node.parentNode" title="Permalink to this definition">¶</a></dt>
<dd>The parent of the current node, or <tt class="xref docutils literal"><span class="pre">None</span></tt> for the document node. The value is
always a <tt class="xref docutils literal"><span class="pre">Node</span></tt> object or <tt class="xref docutils literal"><span class="pre">None</span></tt>.  For <tt class="xref docutils literal"><span class="pre">Element</span></tt> nodes, this
will be the parent element, except for the root element, in which case it will
be the <tt class="xref docutils literal"><span class="pre">Document</span></tt> object. For <tt class="xref docutils literal"><span class="pre">Attr</span></tt> nodes, this is always
<tt class="xref docutils literal"><span class="pre">None</span></tt>. This is a read-only attribute.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.Node.attributes">
<tt class="descclassname">Node.</tt><tt class="descname">attributes</tt><a class="headerlink" href="#xml.dom.Node.attributes" title="Permalink to this definition">¶</a></dt>
<dd>A <tt class="xref docutils literal"><span class="pre">NamedNodeMap</span></tt> of attribute objects.  Only elements have actual values
for this; others provide <tt class="xref docutils literal"><span class="pre">None</span></tt> for this attribute. This is a read-only
attribute.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.Node.previousSibling">
<tt class="descclassname">Node.</tt><tt class="descname">previousSibling</tt><a class="headerlink" href="#xml.dom.Node.previousSibling" title="Permalink to this definition">¶</a></dt>
<dd>The node that immediately precedes this one with the same parent.  For
instance the element with an end-tag that comes just before the <em>self</em>
element&#8217;s start-tag.  Of course, XML documents are made up of more than just
elements so the previous sibling could be text, a comment, or something else.
If this node is the first child of the parent, this attribute will be
<tt class="xref docutils literal"><span class="pre">None</span></tt>. This is a read-only attribute.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.Node.nextSibling">
<tt class="descclassname">Node.</tt><tt class="descname">nextSibling</tt><a class="headerlink" href="#xml.dom.Node.nextSibling" title="Permalink to this definition">¶</a></dt>
<dd>The node that immediately follows this one with the same parent.  See also
<a title="xml.dom.Node.previousSibling" class="reference internal" href="#xml.dom.Node.previousSibling"><tt class="xref docutils literal"><span class="pre">previousSibling</span></tt></a>.  If this is the last child of the parent, this
attribute will be <tt class="xref docutils literal"><span class="pre">None</span></tt>. This is a read-only attribute.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.Node.childNodes">
<tt class="descclassname">Node.</tt><tt class="descname">childNodes</tt><a class="headerlink" href="#xml.dom.Node.childNodes" title="Permalink to this definition">¶</a></dt>
<dd>A list of nodes contained within this node. This is a read-only attribute.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.Node.firstChild">
<tt class="descclassname">Node.</tt><tt class="descname">firstChild</tt><a class="headerlink" href="#xml.dom.Node.firstChild" title="Permalink to this definition">¶</a></dt>
<dd>The first child of the node, if there are any, or <tt class="xref docutils literal"><span class="pre">None</span></tt>. This is a read-only
attribute.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.Node.lastChild">
<tt class="descclassname">Node.</tt><tt class="descname">lastChild</tt><a class="headerlink" href="#xml.dom.Node.lastChild" title="Permalink to this definition">¶</a></dt>
<dd>The last child of the node, if there are any, or <tt class="xref docutils literal"><span class="pre">None</span></tt>. This is a read-only
attribute.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.Node.localName">
<tt class="descclassname">Node.</tt><tt class="descname">localName</tt><a class="headerlink" href="#xml.dom.Node.localName" title="Permalink to this definition">¶</a></dt>
<dd>The part of the <tt class="xref docutils literal"><span class="pre">tagName</span></tt> following the colon if there is one, else the
entire <tt class="xref docutils literal"><span class="pre">tagName</span></tt>.  The value is a string.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.Node.prefix">
<tt class="descclassname">Node.</tt><tt class="descname">prefix</tt><a class="headerlink" href="#xml.dom.Node.prefix" title="Permalink to this definition">¶</a></dt>
<dd>The part of the <tt class="xref docutils literal"><span class="pre">tagName</span></tt> preceding the colon if there is one, else the
empty string.  The value is a string, or <tt class="xref docutils literal"><span class="pre">None</span></tt></dd></dl>

<dl class="attribute">
<dt id="xml.dom.Node.namespaceURI">
<tt class="descclassname">Node.</tt><tt class="descname">namespaceURI</tt><a class="headerlink" href="#xml.dom.Node.namespaceURI" title="Permalink to this definition">¶</a></dt>
<dd>The namespace associated with the element name.  This will be a string or
<tt class="xref docutils literal"><span class="pre">None</span></tt>.  This is a read-only attribute.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.Node.nodeName">
<tt class="descclassname">Node.</tt><tt class="descname">nodeName</tt><a class="headerlink" href="#xml.dom.Node.nodeName" title="Permalink to this definition">¶</a></dt>
<dd>This has a different meaning for each node type; see the DOM specification for
details.  You can always get the information you would get here from another
property such as the <tt class="xref docutils literal"><span class="pre">tagName</span></tt> property for elements or the <tt class="xref docutils literal"><span class="pre">name</span></tt>
property for attributes. For all node types, the value of this attribute will be
either a string or <tt class="xref docutils literal"><span class="pre">None</span></tt>.  This is a read-only attribute.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.Node.nodeValue">
<tt class="descclassname">Node.</tt><tt class="descname">nodeValue</tt><a class="headerlink" href="#xml.dom.Node.nodeValue" title="Permalink to this definition">¶</a></dt>
<dd>This has a different meaning for each node type; see the DOM specification for
details.  The situation is similar to that with <a title="xml.dom.Node.nodeName" class="reference internal" href="#xml.dom.Node.nodeName"><tt class="xref docutils literal"><span class="pre">nodeName</span></tt></a>.  The value is
a string or <tt class="xref docutils literal"><span class="pre">None</span></tt>.</dd></dl>

<dl class="method">
<dt id="xml.dom.Node.hasAttributes">
<tt class="descclassname">Node.</tt><tt class="descname">hasAttributes</tt><big>(</big><big>)</big><a class="headerlink" href="#xml.dom.Node.hasAttributes" title="Permalink to this definition">¶</a></dt>
<dd>Returns true if the node has any attributes.</dd></dl>

<dl class="method">
<dt id="xml.dom.Node.hasChildNodes">
<tt class="descclassname">Node.</tt><tt class="descname">hasChildNodes</tt><big>(</big><big>)</big><a class="headerlink" href="#xml.dom.Node.hasChildNodes" title="Permalink to this definition">¶</a></dt>
<dd>Returns true if the node has any child nodes.</dd></dl>

<dl class="method">
<dt id="xml.dom.Node.isSameNode">
<tt class="descclassname">Node.</tt><tt class="descname">isSameNode</tt><big>(</big><em>other</em><big>)</big><a class="headerlink" href="#xml.dom.Node.isSameNode" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns true if <em>other</em> refers to the same node as this node. This is especially
useful for DOM implementations which use any sort of proxy architecture (because
more than one object can refer to the same node).</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">This is based on a proposed DOM Level 3 API which is still in the &#8220;working
draft&#8221; stage, but this particular interface appears uncontroversial.  Changes
from the W3C will not necessarily affect this method in the Python DOM interface
(though any new W3C API for this would also be supported).</p>
</div>
</dd></dl>

<dl class="method">
<dt id="xml.dom.Node.appendChild">
<tt class="descclassname">Node.</tt><tt class="descname">appendChild</tt><big>(</big><em>newChild</em><big>)</big><a class="headerlink" href="#xml.dom.Node.appendChild" title="Permalink to this definition">¶</a></dt>
<dd>Add a new child node to this node at the end of the list of
children, returning <em>newChild</em>. If the node was already in
in the tree, it is removed first.</dd></dl>

<dl class="method">
<dt id="xml.dom.Node.insertBefore">
<tt class="descclassname">Node.</tt><tt class="descname">insertBefore</tt><big>(</big><em>newChild</em>, <em>refChild</em><big>)</big><a class="headerlink" href="#xml.dom.Node.insertBefore" title="Permalink to this definition">¶</a></dt>
<dd>Insert a new child node before an existing child.  It must be the case that
<em>refChild</em> is a child of this node; if not, <a title="exceptions.ValueError" class="reference external" href="exceptions.html#exceptions.ValueError"><tt class="xref docutils literal"><span class="pre">ValueError</span></tt></a> is raised.
<em>newChild</em> is returned. If <em>refChild</em> is <tt class="xref docutils literal"><span class="pre">None</span></tt>, it inserts <em>newChild</em> at the
end of the children&#8217;s list.</dd></dl>

<dl class="method">
<dt id="xml.dom.Node.removeChild">
<tt class="descclassname">Node.</tt><tt class="descname">removeChild</tt><big>(</big><em>oldChild</em><big>)</big><a class="headerlink" href="#xml.dom.Node.removeChild" title="Permalink to this definition">¶</a></dt>
<dd>Remove a child node.  <em>oldChild</em> must be a child of this node; if not,
<a title="exceptions.ValueError" class="reference external" href="exceptions.html#exceptions.ValueError"><tt class="xref docutils literal"><span class="pre">ValueError</span></tt></a> is raised.  <em>oldChild</em> is returned on success.  If <em>oldChild</em>
will not be used further, its <tt class="xref docutils literal"><span class="pre">unlink()</span></tt> method should be called.</dd></dl>

<dl class="method">
<dt id="xml.dom.Node.replaceChild">
<tt class="descclassname">Node.</tt><tt class="descname">replaceChild</tt><big>(</big><em>newChild</em>, <em>oldChild</em><big>)</big><a class="headerlink" href="#xml.dom.Node.replaceChild" title="Permalink to this definition">¶</a></dt>
<dd>Replace an existing node with a new node. It must be the case that  <em>oldChild</em>
is a child of this node; if not, <a title="exceptions.ValueError" class="reference external" href="exceptions.html#exceptions.ValueError"><tt class="xref docutils literal"><span class="pre">ValueError</span></tt></a> is raised.</dd></dl>

<dl class="method">
<dt id="xml.dom.Node.normalize">
<tt class="descclassname">Node.</tt><tt class="descname">normalize</tt><big>(</big><big>)</big><a class="headerlink" href="#xml.dom.Node.normalize" title="Permalink to this definition">¶</a></dt>
<dd><p>Join adjacent text nodes so that all stretches of text are stored as single
<tt class="xref docutils literal"><span class="pre">Text</span></tt> instances.  This simplifies processing text from a DOM tree for
many applications.</p>
<p>
<span class="versionmodified">New in version 2.1.</span></p>
</dd></dl>

<dl class="method">
<dt id="xml.dom.Node.cloneNode">
<tt class="descclassname">Node.</tt><tt class="descname">cloneNode</tt><big>(</big><em>deep</em><big>)</big><a class="headerlink" href="#xml.dom.Node.cloneNode" title="Permalink to this definition">¶</a></dt>
<dd>Clone this node.  Setting <em>deep</em> means to clone all child nodes as well.  This
returns the clone.</dd></dl>

</div>
<div class="section" id="nodelist-objects">
<span id="dom-nodelist-objects"></span><h3>20.6.2.3. NodeList Objects<a class="headerlink" href="#nodelist-objects" title="Permalink to this headline">¶</a></h3>
<p>A <tt class="xref docutils literal"><span class="pre">NodeList</span></tt> represents a sequence of nodes.  These objects are used in
two ways in the DOM Core recommendation:  the <tt class="xref docutils literal"><span class="pre">Element</span></tt> objects provides
one as its list of child nodes, and the <tt class="xref docutils literal"><span class="pre">getElementsByTagName()</span></tt> and
<tt class="xref docutils literal"><span class="pre">getElementsByTagNameNS()</span></tt> methods of <tt class="xref docutils literal"><span class="pre">Node</span></tt> return objects with this
interface to represent query results.</p>
<p>The DOM Level 2 recommendation defines one method and one attribute for these
objects:</p>
<dl class="method">
<dt id="xml.dom.NodeList.item">
<tt class="descclassname">NodeList.</tt><tt class="descname">item</tt><big>(</big><em>i</em><big>)</big><a class="headerlink" href="#xml.dom.NodeList.item" title="Permalink to this definition">¶</a></dt>
<dd>Return the <em>i</em>&#8216;th item from the sequence, if there is one, or <tt class="xref docutils literal"><span class="pre">None</span></tt>.  The
index <em>i</em> is not allowed to be less then zero or greater than or equal to the
length of the sequence.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.NodeList.length">
<tt class="descclassname">NodeList.</tt><tt class="descname">length</tt><a class="headerlink" href="#xml.dom.NodeList.length" title="Permalink to this definition">¶</a></dt>
<dd>The number of nodes in the sequence.</dd></dl>

<p>In addition, the Python DOM interface requires that some additional support is
provided to allow <tt class="xref docutils literal"><span class="pre">NodeList</span></tt> objects to be used as Python sequences.  All
<tt class="xref docutils literal"><span class="pre">NodeList</span></tt> implementations must include support for <a title="object.__len__" class="reference external" href="../reference/datamodel.html#object.__len__"><tt class="xref docutils literal"><span class="pre">__len__()</span></tt></a> and
<a title="object.__getitem__" class="reference external" href="../reference/datamodel.html#object.__getitem__"><tt class="xref docutils literal"><span class="pre">__getitem__()</span></tt></a>; this allows iteration over the <tt class="xref docutils literal"><span class="pre">NodeList</span></tt> in
<a class="reference external" href="../reference/compound_stmts.html#for"><tt class="xref docutils literal"><span class="pre">for</span></tt></a> statements and proper support for the <a title="len" class="reference external" href="functions.html#len"><tt class="xref docutils literal"><span class="pre">len()</span></tt></a> built-in
function.</p>
<p>If a DOM implementation supports modification of the document, the
<tt class="xref docutils literal"><span class="pre">NodeList</span></tt> implementation must also support the <a title="object.__setitem__" class="reference external" href="../reference/datamodel.html#object.__setitem__"><tt class="xref docutils literal"><span class="pre">__setitem__()</span></tt></a> and
<a title="object.__delitem__" class="reference external" href="../reference/datamodel.html#object.__delitem__"><tt class="xref docutils literal"><span class="pre">__delitem__()</span></tt></a> methods.</p>
</div>
<div class="section" id="documenttype-objects">
<span id="dom-documenttype-objects"></span><h3>20.6.2.4. DocumentType Objects<a class="headerlink" href="#documenttype-objects" title="Permalink to this headline">¶</a></h3>
<p>Information about the notations and entities declared by a document (including
the external subset if the parser uses it and can provide the information) is
available from a <tt class="xref docutils literal"><span class="pre">DocumentType</span></tt> object.  The <tt class="xref docutils literal"><span class="pre">DocumentType</span></tt> for a
document is available from the <tt class="xref docutils literal"><span class="pre">Document</span></tt> object&#8217;s <tt class="xref docutils literal"><span class="pre">doctype</span></tt>
attribute; if there is no <tt class="docutils literal"><span class="pre">DOCTYPE</span></tt> declaration for the document, the
document&#8217;s <tt class="xref docutils literal"><span class="pre">doctype</span></tt> attribute will be set to <tt class="xref docutils literal"><span class="pre">None</span></tt> instead of an
instance of this interface.</p>
<p><tt class="xref docutils literal"><span class="pre">DocumentType</span></tt> is a specialization of <tt class="xref docutils literal"><span class="pre">Node</span></tt>, and adds the
following attributes:</p>
<dl class="attribute">
<dt id="xml.dom.DocumentType.publicId">
<tt class="descclassname">DocumentType.</tt><tt class="descname">publicId</tt><a class="headerlink" href="#xml.dom.DocumentType.publicId" title="Permalink to this definition">¶</a></dt>
<dd>The public identifier for the external subset of the document type definition.
This will be a string or <tt class="xref docutils literal"><span class="pre">None</span></tt>.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.DocumentType.systemId">
<tt class="descclassname">DocumentType.</tt><tt class="descname">systemId</tt><a class="headerlink" href="#xml.dom.DocumentType.systemId" title="Permalink to this definition">¶</a></dt>
<dd>The system identifier for the external subset of the document type definition.
This will be a URI as a string, or <tt class="xref docutils literal"><span class="pre">None</span></tt>.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.DocumentType.internalSubset">
<tt class="descclassname">DocumentType.</tt><tt class="descname">internalSubset</tt><a class="headerlink" href="#xml.dom.DocumentType.internalSubset" title="Permalink to this definition">¶</a></dt>
<dd>A string giving the complete internal subset from the document. This does not
include the brackets which enclose the subset.  If the document has no internal
subset, this should be <tt class="xref docutils literal"><span class="pre">None</span></tt>.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.DocumentType.name">
<tt class="descclassname">DocumentType.</tt><tt class="descname">name</tt><a class="headerlink" href="#xml.dom.DocumentType.name" title="Permalink to this definition">¶</a></dt>
<dd>The name of the root element as given in the <tt class="docutils literal"><span class="pre">DOCTYPE</span></tt> declaration, if
present.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.DocumentType.entities">
<tt class="descclassname">DocumentType.</tt><tt class="descname">entities</tt><a class="headerlink" href="#xml.dom.DocumentType.entities" title="Permalink to this definition">¶</a></dt>
<dd>This is a <tt class="xref docutils literal"><span class="pre">NamedNodeMap</span></tt> giving the definitions of external entities.
For entity names defined more than once, only the first definition is provided
(others are ignored as required by the XML recommendation).  This may be
<tt class="xref docutils literal"><span class="pre">None</span></tt> if the information is not provided by the parser, or if no entities are
defined.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.DocumentType.notations">
<tt class="descclassname">DocumentType.</tt><tt class="descname">notations</tt><a class="headerlink" href="#xml.dom.DocumentType.notations" title="Permalink to this definition">¶</a></dt>
<dd>This is a <tt class="xref docutils literal"><span class="pre">NamedNodeMap</span></tt> giving the definitions of notations. For
notation names defined more than once, only the first definition is provided
(others are ignored as required by the XML recommendation).  This may be
<tt class="xref docutils literal"><span class="pre">None</span></tt> if the information is not provided by the parser, or if no notations
are defined.</dd></dl>

</div>
<div class="section" id="document-objects">
<span id="dom-document-objects"></span><h3>20.6.2.5. Document Objects<a class="headerlink" href="#document-objects" title="Permalink to this headline">¶</a></h3>
<p>A <tt class="xref docutils literal"><span class="pre">Document</span></tt> represents an entire XML document, including its constituent
elements, attributes, processing instructions, comments etc.  Remember that it
inherits properties from <tt class="xref docutils literal"><span class="pre">Node</span></tt>.</p>
<dl class="attribute">
<dt id="xml.dom.Document.documentElement">
<tt class="descclassname">Document.</tt><tt class="descname">documentElement</tt><a class="headerlink" href="#xml.dom.Document.documentElement" title="Permalink to this definition">¶</a></dt>
<dd>The one and only root element of the document.</dd></dl>

<dl class="method">
<dt id="xml.dom.Document.createElement">
<tt class="descclassname">Document.</tt><tt class="descname">createElement</tt><big>(</big><em>tagName</em><big>)</big><a class="headerlink" href="#xml.dom.Document.createElement" title="Permalink to this definition">¶</a></dt>
<dd>Create and return a new element node.  The element is not inserted into the
document when it is created.  You need to explicitly insert it with one of the
other methods such as <tt class="xref docutils literal"><span class="pre">insertBefore()</span></tt> or <tt class="xref docutils literal"><span class="pre">appendChild()</span></tt>.</dd></dl>

<dl class="method">
<dt id="xml.dom.Document.createElementNS">
<tt class="descclassname">Document.</tt><tt class="descname">createElementNS</tt><big>(</big><em>namespaceURI</em>, <em>tagName</em><big>)</big><a class="headerlink" href="#xml.dom.Document.createElementNS" title="Permalink to this definition">¶</a></dt>
<dd>Create and return a new element with a namespace.  The <em>tagName</em> may have a
prefix.  The element is not inserted into the document when it is created.  You
need to explicitly insert it with one of the other methods such as
<tt class="xref docutils literal"><span class="pre">insertBefore()</span></tt> or <tt class="xref docutils literal"><span class="pre">appendChild()</span></tt>.</dd></dl>

<dl class="method">
<dt id="xml.dom.Document.createTextNode">
<tt class="descclassname">Document.</tt><tt class="descname">createTextNode</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#xml.dom.Document.createTextNode" title="Permalink to this definition">¶</a></dt>
<dd>Create and return a text node containing the data passed as a parameter.  As
with the other creation methods, this one does not insert the node into the
tree.</dd></dl>

<dl class="method">
<dt id="xml.dom.Document.createComment">
<tt class="descclassname">Document.</tt><tt class="descname">createComment</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#xml.dom.Document.createComment" title="Permalink to this definition">¶</a></dt>
<dd>Create and return a comment node containing the data passed as a parameter.  As
with the other creation methods, this one does not insert the node into the
tree.</dd></dl>

<dl class="method">
<dt id="xml.dom.Document.createProcessingInstruction">
<tt class="descclassname">Document.</tt><tt class="descname">createProcessingInstruction</tt><big>(</big><em>target</em>, <em>data</em><big>)</big><a class="headerlink" href="#xml.dom.Document.createProcessingInstruction" title="Permalink to this definition">¶</a></dt>
<dd>Create and return a processing instruction node containing the <em>target</em> and
<em>data</em> passed as parameters.  As with the other creation methods, this one does
not insert the node into the tree.</dd></dl>

<dl class="method">
<dt id="xml.dom.Document.createAttribute">
<tt class="descclassname">Document.</tt><tt class="descname">createAttribute</tt><big>(</big><em>name</em><big>)</big><a class="headerlink" href="#xml.dom.Document.createAttribute" title="Permalink to this definition">¶</a></dt>
<dd>Create and return an attribute node.  This method does not associate the
attribute node with any particular element.  You must use
<tt class="xref docutils literal"><span class="pre">setAttributeNode()</span></tt> on the appropriate <tt class="xref docutils literal"><span class="pre">Element</span></tt> object to use the
newly created attribute instance.</dd></dl>

<dl class="method">
<dt id="xml.dom.Document.createAttributeNS">
<tt class="descclassname">Document.</tt><tt class="descname">createAttributeNS</tt><big>(</big><em>namespaceURI</em>, <em>qualifiedName</em><big>)</big><a class="headerlink" href="#xml.dom.Document.createAttributeNS" title="Permalink to this definition">¶</a></dt>
<dd>Create and return an attribute node with a namespace.  The <em>tagName</em> may have a
prefix.  This method does not associate the attribute node with any particular
element.  You must use <tt class="xref docutils literal"><span class="pre">setAttributeNode()</span></tt> on the appropriate
<tt class="xref docutils literal"><span class="pre">Element</span></tt> object to use the newly created attribute instance.</dd></dl>

<dl class="method">
<dt id="xml.dom.Document.getElementsByTagName">
<tt class="descclassname">Document.</tt><tt class="descname">getElementsByTagName</tt><big>(</big><em>tagName</em><big>)</big><a class="headerlink" href="#xml.dom.Document.getElementsByTagName" title="Permalink to this definition">¶</a></dt>
<dd>Search for all descendants (direct children, children&#8217;s children, etc.) with a
particular element type name.</dd></dl>

<dl class="method">
<dt id="xml.dom.Document.getElementsByTagNameNS">
<tt class="descclassname">Document.</tt><tt class="descname">getElementsByTagNameNS</tt><big>(</big><em>namespaceURI</em>, <em>localName</em><big>)</big><a class="headerlink" href="#xml.dom.Document.getElementsByTagNameNS" title="Permalink to this definition">¶</a></dt>
<dd>Search for all descendants (direct children, children&#8217;s children, etc.) with a
particular namespace URI and localname.  The localname is the part of the
namespace after the prefix.</dd></dl>

</div>
<div class="section" id="element-objects">
<span id="dom-element-objects"></span><h3>20.6.2.6. Element Objects<a class="headerlink" href="#element-objects" title="Permalink to this headline">¶</a></h3>
<p><tt class="xref docutils literal"><span class="pre">Element</span></tt> is a subclass of <tt class="xref docutils literal"><span class="pre">Node</span></tt>, so inherits all the attributes
of that class.</p>
<dl class="attribute">
<dt id="xml.dom.Element.tagName">
<tt class="descclassname">Element.</tt><tt class="descname">tagName</tt><a class="headerlink" href="#xml.dom.Element.tagName" title="Permalink to this definition">¶</a></dt>
<dd>The element type name.  In a namespace-using document it may have colons in it.
The value is a string.</dd></dl>

<dl class="method">
<dt id="xml.dom.Element.getElementsByTagName">
<tt class="descclassname">Element.</tt><tt class="descname">getElementsByTagName</tt><big>(</big><em>tagName</em><big>)</big><a class="headerlink" href="#xml.dom.Element.getElementsByTagName" title="Permalink to this definition">¶</a></dt>
<dd>Same as equivalent method in the <tt class="xref docutils literal"><span class="pre">Document</span></tt> class.</dd></dl>

<dl class="method">
<dt id="xml.dom.Element.getElementsByTagNameNS">
<tt class="descclassname">Element.</tt><tt class="descname">getElementsByTagNameNS</tt><big>(</big><em>namespaceURI</em>, <em>localName</em><big>)</big><a class="headerlink" href="#xml.dom.Element.getElementsByTagNameNS" title="Permalink to this definition">¶</a></dt>
<dd>Same as equivalent method in the <tt class="xref docutils literal"><span class="pre">Document</span></tt> class.</dd></dl>

<dl class="method">
<dt id="xml.dom.Element.hasAttribute">
<tt class="descclassname">Element.</tt><tt class="descname">hasAttribute</tt><big>(</big><em>name</em><big>)</big><a class="headerlink" href="#xml.dom.Element.hasAttribute" title="Permalink to this definition">¶</a></dt>
<dd>Returns true if the element has an attribute named by <em>name</em>.</dd></dl>

<dl class="method">
<dt id="xml.dom.Element.hasAttributeNS">
<tt class="descclassname">Element.</tt><tt class="descname">hasAttributeNS</tt><big>(</big><em>namespaceURI</em>, <em>localName</em><big>)</big><a class="headerlink" href="#xml.dom.Element.hasAttributeNS" title="Permalink to this definition">¶</a></dt>
<dd>Returns true if the element has an attribute named by <em>namespaceURI</em> and
<em>localName</em>.</dd></dl>

<dl class="method">
<dt id="xml.dom.Element.getAttribute">
<tt class="descclassname">Element.</tt><tt class="descname">getAttribute</tt><big>(</big><em>name</em><big>)</big><a class="headerlink" href="#xml.dom.Element.getAttribute" title="Permalink to this definition">¶</a></dt>
<dd>Return the value of the attribute named by <em>name</em> as a string. If no such
attribute exists, an empty string is returned, as if the attribute had no value.</dd></dl>

<dl class="method">
<dt id="xml.dom.Element.getAttributeNode">
<tt class="descclassname">Element.</tt><tt class="descname">getAttributeNode</tt><big>(</big><em>attrname</em><big>)</big><a class="headerlink" href="#xml.dom.Element.getAttributeNode" title="Permalink to this definition">¶</a></dt>
<dd>Return the <tt class="xref docutils literal"><span class="pre">Attr</span></tt> node for the attribute named by <em>attrname</em>.</dd></dl>

<dl class="method">
<dt id="xml.dom.Element.getAttributeNS">
<tt class="descclassname">Element.</tt><tt class="descname">getAttributeNS</tt><big>(</big><em>namespaceURI</em>, <em>localName</em><big>)</big><a class="headerlink" href="#xml.dom.Element.getAttributeNS" title="Permalink to this definition">¶</a></dt>
<dd>Return the value of the attribute named by <em>namespaceURI</em> and <em>localName</em> as a
string. If no such attribute exists, an empty string is returned, as if the
attribute had no value.</dd></dl>

<dl class="method">
<dt id="xml.dom.Element.getAttributeNodeNS">
<tt class="descclassname">Element.</tt><tt class="descname">getAttributeNodeNS</tt><big>(</big><em>namespaceURI</em>, <em>localName</em><big>)</big><a class="headerlink" href="#xml.dom.Element.getAttributeNodeNS" title="Permalink to this definition">¶</a></dt>
<dd>Return an attribute value as a node, given a <em>namespaceURI</em> and <em>localName</em>.</dd></dl>

<dl class="method">
<dt id="xml.dom.Element.removeAttribute">
<tt class="descclassname">Element.</tt><tt class="descname">removeAttribute</tt><big>(</big><em>name</em><big>)</big><a class="headerlink" href="#xml.dom.Element.removeAttribute" title="Permalink to this definition">¶</a></dt>
<dd>Remove an attribute by name.  If there is no matching attribute, a
<a title="xml.dom.NotFoundErr" class="reference internal" href="#xml.dom.NotFoundErr"><tt class="xref docutils literal"><span class="pre">NotFoundErr</span></tt></a> is raised.</dd></dl>

<dl class="method">
<dt id="xml.dom.Element.removeAttributeNode">
<tt class="descclassname">Element.</tt><tt class="descname">removeAttributeNode</tt><big>(</big><em>oldAttr</em><big>)</big><a class="headerlink" href="#xml.dom.Element.removeAttributeNode" title="Permalink to this definition">¶</a></dt>
<dd>Remove and return <em>oldAttr</em> from the attribute list, if present. If <em>oldAttr</em> is
not present, <a title="xml.dom.NotFoundErr" class="reference internal" href="#xml.dom.NotFoundErr"><tt class="xref docutils literal"><span class="pre">NotFoundErr</span></tt></a> is raised.</dd></dl>

<dl class="method">
<dt id="xml.dom.Element.removeAttributeNS">
<tt class="descclassname">Element.</tt><tt class="descname">removeAttributeNS</tt><big>(</big><em>namespaceURI</em>, <em>localName</em><big>)</big><a class="headerlink" href="#xml.dom.Element.removeAttributeNS" title="Permalink to this definition">¶</a></dt>
<dd>Remove an attribute by name.  Note that it uses a localName, not a qname.  No
exception is raised if there is no matching attribute.</dd></dl>

<dl class="method">
<dt id="xml.dom.Element.setAttribute">
<tt class="descclassname">Element.</tt><tt class="descname">setAttribute</tt><big>(</big><em>name</em>, <em>value</em><big>)</big><a class="headerlink" href="#xml.dom.Element.setAttribute" title="Permalink to this definition">¶</a></dt>
<dd>Set an attribute value from a string.</dd></dl>

<dl class="method">
<dt id="xml.dom.Element.setAttributeNode">
<tt class="descclassname">Element.</tt><tt class="descname">setAttributeNode</tt><big>(</big><em>newAttr</em><big>)</big><a class="headerlink" href="#xml.dom.Element.setAttributeNode" title="Permalink to this definition">¶</a></dt>
<dd>Add a new attribute node to the element, replacing an existing attribute if
necessary if the <tt class="xref docutils literal"><span class="pre">name</span></tt> attribute matches.  If a replacement occurs, the
old attribute node will be returned.  If <em>newAttr</em> is already in use,
<a title="xml.dom.InuseAttributeErr" class="reference internal" href="#xml.dom.InuseAttributeErr"><tt class="xref docutils literal"><span class="pre">InuseAttributeErr</span></tt></a> will be raised.</dd></dl>

<dl class="method">
<dt id="xml.dom.Element.setAttributeNodeNS">
<tt class="descclassname">Element.</tt><tt class="descname">setAttributeNodeNS</tt><big>(</big><em>newAttr</em><big>)</big><a class="headerlink" href="#xml.dom.Element.setAttributeNodeNS" title="Permalink to this definition">¶</a></dt>
<dd>Add a new attribute node to the element, replacing an existing attribute if
necessary if the <tt class="xref docutils literal"><span class="pre">namespaceURI</span></tt> and <tt class="xref docutils literal"><span class="pre">localName</span></tt> attributes match.
If a replacement occurs, the old attribute node will be returned.  If <em>newAttr</em>
is already in use, <a title="xml.dom.InuseAttributeErr" class="reference internal" href="#xml.dom.InuseAttributeErr"><tt class="xref docutils literal"><span class="pre">InuseAttributeErr</span></tt></a> will be raised.</dd></dl>

<dl class="method">
<dt id="xml.dom.Element.setAttributeNS">
<tt class="descclassname">Element.</tt><tt class="descname">setAttributeNS</tt><big>(</big><em>namespaceURI</em>, <em>qname</em>, <em>value</em><big>)</big><a class="headerlink" href="#xml.dom.Element.setAttributeNS" title="Permalink to this definition">¶</a></dt>
<dd>Set an attribute value from a string, given a <em>namespaceURI</em> and a <em>qname</em>.
Note that a qname is the whole attribute name.  This is different than above.</dd></dl>

</div>
<div class="section" id="attr-objects">
<span id="dom-attr-objects"></span><h3>20.6.2.7. Attr Objects<a class="headerlink" href="#attr-objects" title="Permalink to this headline">¶</a></h3>
<p><tt class="xref docutils literal"><span class="pre">Attr</span></tt> inherits from <tt class="xref docutils literal"><span class="pre">Node</span></tt>, so inherits all its attributes.</p>
<dl class="attribute">
<dt id="xml.dom.Attr.name">
<tt class="descclassname">Attr.</tt><tt class="descname">name</tt><a class="headerlink" href="#xml.dom.Attr.name" title="Permalink to this definition">¶</a></dt>
<dd>The attribute name.  In a namespace-using document it may have colons in it.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.Attr.localName">
<tt class="descclassname">Attr.</tt><tt class="descname">localName</tt><a class="headerlink" href="#xml.dom.Attr.localName" title="Permalink to this definition">¶</a></dt>
<dd>The part of the name following the colon if there is one, else the entire name.
This is a read-only attribute.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.Attr.prefix">
<tt class="descclassname">Attr.</tt><tt class="descname">prefix</tt><a class="headerlink" href="#xml.dom.Attr.prefix" title="Permalink to this definition">¶</a></dt>
<dd>The part of the name preceding the colon if there is one, else the empty string.</dd></dl>

</div>
<div class="section" id="namednodemap-objects">
<span id="dom-attributelist-objects"></span><h3>20.6.2.8. NamedNodeMap Objects<a class="headerlink" href="#namednodemap-objects" title="Permalink to this headline">¶</a></h3>
<p><tt class="xref docutils literal"><span class="pre">NamedNodeMap</span></tt> does <em>not</em> inherit from <tt class="xref docutils literal"><span class="pre">Node</span></tt>.</p>
<dl class="attribute">
<dt id="xml.dom.NamedNodeMap.length">
<tt class="descclassname">NamedNodeMap.</tt><tt class="descname">length</tt><a class="headerlink" href="#xml.dom.NamedNodeMap.length" title="Permalink to this definition">¶</a></dt>
<dd>The length of the attribute list.</dd></dl>

<dl class="method">
<dt id="xml.dom.NamedNodeMap.item">
<tt class="descclassname">NamedNodeMap.</tt><tt class="descname">item</tt><big>(</big><em>index</em><big>)</big><a class="headerlink" href="#xml.dom.NamedNodeMap.item" title="Permalink to this definition">¶</a></dt>
<dd>Return an attribute with a particular index.  The order you get the attributes
in is arbitrary but will be consistent for the life of a DOM.  Each item is an
attribute node.  Get its value with the <tt class="xref docutils literal"><span class="pre">value</span></tt> attribute.</dd></dl>

<p>There are also experimental methods that give this class more mapping behavior.
You can use them or you can use the standardized <tt class="xref docutils literal"><span class="pre">getAttribute*()</span></tt> family
of methods on the <tt class="xref docutils literal"><span class="pre">Element</span></tt> objects.</p>
</div>
<div class="section" id="comment-objects">
<span id="dom-comment-objects"></span><h3>20.6.2.9. Comment Objects<a class="headerlink" href="#comment-objects" title="Permalink to this headline">¶</a></h3>
<p><tt class="xref docutils literal"><span class="pre">Comment</span></tt> represents a comment in the XML document.  It is a subclass of
<tt class="xref docutils literal"><span class="pre">Node</span></tt>, but cannot have child nodes.</p>
<dl class="attribute">
<dt id="xml.dom.Comment.data">
<tt class="descclassname">Comment.</tt><tt class="descname">data</tt><a class="headerlink" href="#xml.dom.Comment.data" title="Permalink to this definition">¶</a></dt>
<dd>The content of the comment as a string.  The attribute contains all characters
between the leading <tt class="docutils literal"><span class="pre">&lt;!-</span></tt><tt class="docutils literal"><span class="pre">-</span></tt> and trailing <tt class="docutils literal"><span class="pre">-</span></tt><tt class="docutils literal"><span class="pre">-&gt;</span></tt>, but does not
include them.</dd></dl>

</div>
<div class="section" id="text-and-cdatasection-objects">
<span id="dom-text-objects"></span><h3>20.6.2.10. Text and CDATASection Objects<a class="headerlink" href="#text-and-cdatasection-objects" title="Permalink to this headline">¶</a></h3>
<p>The <tt class="xref docutils literal"><span class="pre">Text</span></tt> interface represents text in the XML document.  If the parser
and DOM implementation support the DOM&#8217;s XML extension, portions of the text
enclosed in CDATA marked sections are stored in <tt class="xref docutils literal"><span class="pre">CDATASection</span></tt> objects.
These two interfaces are identical, but provide different values for the
<tt class="xref docutils literal"><span class="pre">nodeType</span></tt> attribute.</p>
<p>These interfaces extend the <tt class="xref docutils literal"><span class="pre">Node</span></tt> interface.  They cannot have child
nodes.</p>
<dl class="attribute">
<dt id="xml.dom.Text.data">
<tt class="descclassname">Text.</tt><tt class="descname">data</tt><a class="headerlink" href="#xml.dom.Text.data" title="Permalink to this definition">¶</a></dt>
<dd>The content of the text node as a string.</dd></dl>

<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">The use of a <tt class="xref docutils literal"><span class="pre">CDATASection</span></tt> node does not indicate that the node
represents a complete CDATA marked section, only that the content of the node
was part of a CDATA section.  A single CDATA section may be represented by more
than one node in the document tree.  There is no way to determine whether two
adjacent <tt class="xref docutils literal"><span class="pre">CDATASection</span></tt> nodes represent different CDATA marked sections.</p>
</div>
</div>
<div class="section" id="processinginstruction-objects">
<span id="dom-pi-objects"></span><h3>20.6.2.11. ProcessingInstruction Objects<a class="headerlink" href="#processinginstruction-objects" title="Permalink to this headline">¶</a></h3>
<p>Represents a processing instruction in the XML document; this inherits from the
<tt class="xref docutils literal"><span class="pre">Node</span></tt> interface and cannot have child nodes.</p>
<dl class="attribute">
<dt id="xml.dom.ProcessingInstruction.target">
<tt class="descclassname">ProcessingInstruction.</tt><tt class="descname">target</tt><a class="headerlink" href="#xml.dom.ProcessingInstruction.target" title="Permalink to this definition">¶</a></dt>
<dd>The content of the processing instruction up to the first whitespace character.
This is a read-only attribute.</dd></dl>

<dl class="attribute">
<dt id="xml.dom.ProcessingInstruction.data">
<tt class="descclassname">ProcessingInstruction.</tt><tt class="descname">data</tt><a class="headerlink" href="#xml.dom.ProcessingInstruction.data" title="Permalink to this definition">¶</a></dt>
<dd>The content of the processing instruction following the first whitespace
character.</dd></dl>

</div>
<div class="section" id="exceptions">
<span id="dom-exceptions"></span><h3>20.6.2.12. Exceptions<a class="headerlink" href="#exceptions" title="Permalink to this headline">¶</a></h3>
<p>
<span class="versionmodified">New in version 2.1.</span></p>
<p>The DOM Level 2 recommendation defines a single exception, <a title="xml.dom.DOMException" class="reference internal" href="#xml.dom.DOMException"><tt class="xref docutils literal"><span class="pre">DOMException</span></tt></a>,
and a number of constants that allow applications to determine what sort of
error occurred. <a title="xml.dom.DOMException" class="reference internal" href="#xml.dom.DOMException"><tt class="xref docutils literal"><span class="pre">DOMException</span></tt></a> instances carry a <tt class="xref docutils literal"><span class="pre">code</span></tt> attribute
that provides the appropriate value for the specific exception.</p>
<p>The Python DOM interface provides the constants, but also expands the set of
exceptions so that a specific exception exists for each of the exception codes
defined by the DOM.  The implementations must raise the appropriate specific
exception, each of which carries the appropriate value for the <tt class="xref docutils literal"><span class="pre">code</span></tt>
attribute.</p>
<dl class="exception">
<dt id="xml.dom.DOMException">
<em class="property">
exception </em><tt class="descclassname">xml.dom.</tt><tt class="descname">DOMException</tt><a class="headerlink" href="#xml.dom.DOMException" title="Permalink to this definition">¶</a></dt>
<dd>Base exception class used for all specific DOM exceptions.  This exception class
cannot be directly instantiated.</dd></dl>

<dl class="exception">
<dt id="xml.dom.DomstringSizeErr">
<em class="property">
exception </em><tt class="descclassname">xml.dom.</tt><tt class="descname">DomstringSizeErr</tt><a class="headerlink" href="#xml.dom.DomstringSizeErr" title="Permalink to this definition">¶</a></dt>
<dd>Raised when a specified range of text does not fit into a string. This is not
known to be used in the Python DOM implementations, but may be received from DOM
implementations not written in Python.</dd></dl>

<dl class="exception">
<dt id="xml.dom.HierarchyRequestErr">
<em class="property">
exception </em><tt class="descclassname">xml.dom.</tt><tt class="descname">HierarchyRequestErr</tt><a class="headerlink" href="#xml.dom.HierarchyRequestErr" title="Permalink to this definition">¶</a></dt>
<dd>Raised when an attempt is made to insert a node where the node type is not
allowed.</dd></dl>

<dl class="exception">
<dt id="xml.dom.IndexSizeErr">
<em class="property">
exception </em><tt class="descclassname">xml.dom.</tt><tt class="descname">IndexSizeErr</tt><a class="headerlink" href="#xml.dom.IndexSizeErr" title="Permalink to this definition">¶</a></dt>
<dd>Raised when an index or size parameter to a method is negative or exceeds the
allowed values.</dd></dl>

<dl class="exception">
<dt id="xml.dom.InuseAttributeErr">
<em class="property">
exception </em><tt class="descclassname">xml.dom.</tt><tt class="descname">InuseAttributeErr</tt><a class="headerlink" href="#xml.dom.InuseAttributeErr" title="Permalink to this definition">¶</a></dt>
<dd>Raised when an attempt is made to insert an <tt class="xref docutils literal"><span class="pre">Attr</span></tt> node that is already
present elsewhere in the document.</dd></dl>

<dl class="exception">
<dt id="xml.dom.InvalidAccessErr">
<em class="property">
exception </em><tt class="descclassname">xml.dom.</tt><tt class="descname">InvalidAccessErr</tt><a class="headerlink" href="#xml.dom.InvalidAccessErr" title="Permalink to this definition">¶</a></dt>
<dd>Raised if a parameter or an operation is not supported on the underlying object.</dd></dl>

<dl class="exception">
<dt id="xml.dom.InvalidCharacterErr">
<em class="property">
exception </em><tt class="descclassname">xml.dom.</tt><tt class="descname">InvalidCharacterErr</tt><a class="headerlink" href="#xml.dom.InvalidCharacterErr" title="Permalink to this definition">¶</a></dt>
<dd>This exception is raised when a string parameter contains a character that is
not permitted in the context it&#8217;s being used in by the XML 1.0 recommendation.
For example, attempting to create an <tt class="xref docutils literal"><span class="pre">Element</span></tt> node with a space in the
element type name will cause this error to be raised.</dd></dl>

<dl class="exception">
<dt id="xml.dom.InvalidModificationErr">
<em class="property">
exception </em><tt class="descclassname">xml.dom.</tt><tt class="descname">InvalidModificationErr</tt><a class="headerlink" href="#xml.dom.InvalidModificationErr" title="Permalink to this definition">¶</a></dt>
<dd>Raised when an attempt is made to modify the type of a node.</dd></dl>

<dl class="exception">
<dt id="xml.dom.InvalidStateErr">
<em class="property">
exception </em><tt class="descclassname">xml.dom.</tt><tt class="descname">InvalidStateErr</tt><a class="headerlink" href="#xml.dom.InvalidStateErr" title="Permalink to this definition">¶</a></dt>
<dd>Raised when an attempt is made to use an object that is not defined or is no
longer usable.</dd></dl>

<dl class="exception">
<dt id="xml.dom.NamespaceErr">
<em class="property">
exception </em><tt class="descclassname">xml.dom.</tt><tt class="descname">NamespaceErr</tt><a class="headerlink" href="#xml.dom.NamespaceErr" title="Permalink to this definition">¶</a></dt>
<dd>If an attempt is made to change any object in a way that is not permitted with
regard to the <a class="reference external" href="http://www.w3.org/TR/REC-xml-names/">Namespaces in XML</a>
recommendation, this exception is raised.</dd></dl>

<dl class="exception">
<dt id="xml.dom.NotFoundErr">
<em class="property">
exception </em><tt class="descclassname">xml.dom.</tt><tt class="descname">NotFoundErr</tt><a class="headerlink" href="#xml.dom.NotFoundErr" title="Permalink to this definition">¶</a></dt>
<dd>Exception when a node does not exist in the referenced context.  For example,
<tt class="xref docutils literal"><span class="pre">NamedNodeMap.removeNamedItem()</span></tt> will raise this if the node passed in does
not exist in the map.</dd></dl>

<dl class="exception">
<dt id="xml.dom.NotSupportedErr">
<em class="property">
exception </em><tt class="descclassname">xml.dom.</tt><tt class="descname">NotSupportedErr</tt><a class="headerlink" href="#xml.dom.NotSupportedErr" title="Permalink to this definition">¶</a></dt>
<dd>Raised when the implementation does not support the requested type of object or
operation.</dd></dl>

<dl class="exception">
<dt id="xml.dom.NoDataAllowedErr">
<em class="property">
exception </em><tt class="descclassname">xml.dom.</tt><tt class="descname">NoDataAllowedErr</tt><a class="headerlink" href="#xml.dom.NoDataAllowedErr" title="Permalink to this definition">¶</a></dt>
<dd>This is raised if data is specified for a node which does not support data.</dd></dl>

<dl class="exception">
<dt id="xml.dom.NoModificationAllowedErr">
<em class="property">
exception </em><tt class="descclassname">xml.dom.</tt><tt class="descname">NoModificationAllowedErr</tt><a class="headerlink" href="#xml.dom.NoModificationAllowedErr" title="Permalink to this definition">¶</a></dt>
<dd>Raised on attempts to modify an object where modifications are not allowed (such
as for read-only nodes).</dd></dl>

<dl class="exception">
<dt id="xml.dom.SyntaxErr">
<em class="property">
exception </em><tt class="descclassname">xml.dom.</tt><tt class="descname">SyntaxErr</tt><a class="headerlink" href="#xml.dom.SyntaxErr" title="Permalink to this definition">¶</a></dt>
<dd>Raised when an invalid or illegal string is specified.</dd></dl>

<dl class="exception">
<dt id="xml.dom.WrongDocumentErr">
<em class="property">
exception </em><tt class="descclassname">xml.dom.</tt><tt class="descname">WrongDocumentErr</tt><a class="headerlink" href="#xml.dom.WrongDocumentErr" title="Permalink to this definition">¶</a></dt>
<dd>Raised when a node is inserted in a different document than it currently belongs
to, and the implementation does not support migrating the node from one document
to the other.</dd></dl>

<p>The exception codes defined in the DOM recommendation map to the exceptions
described above according to this table:</p>
<table border="1" class="docutils">
<colgroup>
<col width="54%" />
<col width="46%" />
</colgroup>
<thead valign="bottom">
<tr><th class="head">Constant</th>
<th class="head">Exception</th>
</tr>
</thead>
<tbody valign="top">
<tr><td><tt class="xref docutils literal"><span class="pre">DOMSTRING_SIZE_ERR</span></tt></td>
<td><a title="xml.dom.DomstringSizeErr" class="reference internal" href="#xml.dom.DomstringSizeErr"><tt class="xref docutils literal"><span class="pre">DomstringSizeErr</span></tt></a></td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">HIERARCHY_REQUEST_ERR</span></tt></td>
<td><a title="xml.dom.HierarchyRequestErr" class="reference internal" href="#xml.dom.HierarchyRequestErr"><tt class="xref docutils literal"><span class="pre">HierarchyRequestErr</span></tt></a></td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">INDEX_SIZE_ERR</span></tt></td>
<td><a title="xml.dom.IndexSizeErr" class="reference internal" href="#xml.dom.IndexSizeErr"><tt class="xref docutils literal"><span class="pre">IndexSizeErr</span></tt></a></td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">INUSE_ATTRIBUTE_ERR</span></tt></td>
<td><a title="xml.dom.InuseAttributeErr" class="reference internal" href="#xml.dom.InuseAttributeErr"><tt class="xref docutils literal"><span class="pre">InuseAttributeErr</span></tt></a></td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">INVALID_ACCESS_ERR</span></tt></td>
<td><a title="xml.dom.InvalidAccessErr" class="reference internal" href="#xml.dom.InvalidAccessErr"><tt class="xref docutils literal"><span class="pre">InvalidAccessErr</span></tt></a></td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">INVALID_CHARACTER_ERR</span></tt></td>
<td><a title="xml.dom.InvalidCharacterErr" class="reference internal" href="#xml.dom.InvalidCharacterErr"><tt class="xref docutils literal"><span class="pre">InvalidCharacterErr</span></tt></a></td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">INVALID_MODIFICATION_ERR</span></tt></td>
<td><a title="xml.dom.InvalidModificationErr" class="reference internal" href="#xml.dom.InvalidModificationErr"><tt class="xref docutils literal"><span class="pre">InvalidModificationErr</span></tt></a></td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">INVALID_STATE_ERR</span></tt></td>
<td><a title="xml.dom.InvalidStateErr" class="reference internal" href="#xml.dom.InvalidStateErr"><tt class="xref docutils literal"><span class="pre">InvalidStateErr</span></tt></a></td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">NAMESPACE_ERR</span></tt></td>
<td><a title="xml.dom.NamespaceErr" class="reference internal" href="#xml.dom.NamespaceErr"><tt class="xref docutils literal"><span class="pre">NamespaceErr</span></tt></a></td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">NOT_FOUND_ERR</span></tt></td>
<td><a title="xml.dom.NotFoundErr" class="reference internal" href="#xml.dom.NotFoundErr"><tt class="xref docutils literal"><span class="pre">NotFoundErr</span></tt></a></td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">NOT_SUPPORTED_ERR</span></tt></td>
<td><a title="xml.dom.NotSupportedErr" class="reference internal" href="#xml.dom.NotSupportedErr"><tt class="xref docutils literal"><span class="pre">NotSupportedErr</span></tt></a></td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">NO_DATA_ALLOWED_ERR</span></tt></td>
<td><a title="xml.dom.NoDataAllowedErr" class="reference internal" href="#xml.dom.NoDataAllowedErr"><tt class="xref docutils literal"><span class="pre">NoDataAllowedErr</span></tt></a></td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">NO_MODIFICATION_ALLOWED_ERR</span></tt></td>
<td><a title="xml.dom.NoModificationAllowedErr" class="reference internal" href="#xml.dom.NoModificationAllowedErr"><tt class="xref docutils literal"><span class="pre">NoModificationAllowedErr</span></tt></a></td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">SYNTAX_ERR</span></tt></td>
<td><a title="xml.dom.SyntaxErr" class="reference internal" href="#xml.dom.SyntaxErr"><tt class="xref docutils literal"><span class="pre">SyntaxErr</span></tt></a></td>
</tr>
<tr><td><tt class="xref docutils literal"><span class="pre">WRONG_DOCUMENT_ERR</span></tt></td>
<td><a title="xml.dom.WrongDocumentErr" class="reference internal" href="#xml.dom.WrongDocumentErr"><tt class="xref docutils literal"><span class="pre">WrongDocumentErr</span></tt></a></td>
</tr>
</tbody>
</table>
</div>
</div>
<div class="section" id="conformance">
<span id="dom-conformance"></span><h2>20.6.3. Conformance<a class="headerlink" href="#conformance" title="Permalink to this headline">¶</a></h2>
<p>This section describes the conformance requirements and relationships between
the Python DOM API, the W3C DOM recommendations, and the OMG IDL mapping for
Python.</p>
<div class="section" id="type-mapping">
<span id="dom-type-mapping"></span><h3>20.6.3.1. Type Mapping<a class="headerlink" href="#type-mapping" title="Permalink to this headline">¶</a></h3>
<p>The primitive IDL types used in the DOM specification are mapped to Python types
according to the following table.</p>
<table border="1" class="docutils">
<colgroup>
<col width="30%" />
<col width="70%" />
</colgroup>
<thead valign="bottom">
<tr><th class="head">IDL Type</th>
<th class="head">Python Type</th>
</tr>
</thead>
<tbody valign="top">
<tr><td><tt class="docutils literal"><span class="pre">boolean</span></tt></td>
<td><tt class="docutils literal"><span class="pre">IntegerType</span></tt> (with a value of <tt class="docutils literal"><span class="pre">0</span></tt> or
<tt class="docutils literal"><span class="pre">1</span></tt>)</td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">int</span></tt></td>
<td><tt class="docutils literal"><span class="pre">IntegerType</span></tt></td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">long</span> <span class="pre">int</span></tt></td>
<td><tt class="docutils literal"><span class="pre">IntegerType</span></tt></td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">unsigned</span> <span class="pre">int</span></tt></td>
<td><tt class="docutils literal"><span class="pre">IntegerType</span></tt></td>
</tr>
</tbody>
</table>
<p>Additionally, the <tt class="xref docutils literal"><span class="pre">DOMString</span></tt> defined in the recommendation is mapped to
a Python string or Unicode string.  Applications should be able to handle
Unicode whenever a string is returned from the DOM.</p>
<p>The IDL <tt class="docutils literal"><span class="pre">null</span></tt> value is mapped to <tt class="xref docutils literal"><span class="pre">None</span></tt>, which may be accepted or
provided by the implementation whenever <tt class="docutils literal"><span class="pre">null</span></tt> is allowed by the API.</p>
</div>
<div class="section" id="accessor-methods">
<span id="dom-accessor-methods"></span><h3>20.6.3.2. Accessor Methods<a class="headerlink" href="#accessor-methods" title="Permalink to this headline">¶</a></h3>
<p>The mapping from OMG IDL to Python defines accessor functions for IDL
<tt class="docutils literal"><span class="pre">attribute</span></tt> declarations in much the way the Java mapping does.
Mapping the IDL declarations</p>
<div class="highlight-python"><pre>readonly attribute string someValue;
         attribute string anotherValue;</pre>
</div>
<p>yields three accessor functions:  a &#8220;get&#8221; method for <tt class="xref docutils literal"><span class="pre">someValue</span></tt>
(<tt class="xref docutils literal"><span class="pre">_get_someValue()</span></tt>), and &#8220;get&#8221; and &#8220;set&#8221; methods for <tt class="xref docutils literal"><span class="pre">anotherValue</span></tt>
(<tt class="xref docutils literal"><span class="pre">_get_anotherValue()</span></tt> and <tt class="xref docutils literal"><span class="pre">_set_anotherValue()</span></tt>).  The mapping, in
particular, does not require that the IDL attributes are accessible as normal
Python attributes:  <tt class="docutils literal"><span class="pre">object.someValue</span></tt> is <em>not</em> required to work, and may
raise an <a title="exceptions.AttributeError" class="reference external" href="exceptions.html#exceptions.AttributeError"><tt class="xref docutils literal"><span class="pre">AttributeError</span></tt></a>.</p>
<p>The Python DOM API, however, <em>does</em> require that normal attribute access work.
This means that the typical surrogates generated by Python IDL compilers are not
likely to work, and wrapper objects may be needed on the client if the DOM
objects are accessed via CORBA. While this does require some additional
consideration for CORBA DOM clients, the implementers with experience using DOM
over CORBA from Python do not consider this a problem.  Attributes that are
declared <tt class="docutils literal"><span class="pre">readonly</span></tt> may not restrict write access in all DOM
implementations.</p>
<p>In the Python DOM API, accessor functions are not required.  If provided, they
should take the form defined by the Python IDL mapping, but these methods are
considered unnecessary since the attributes are accessible directly from Python.
&#8220;Set&#8221; accessors should never be provided for <tt class="docutils literal"><span class="pre">readonly</span></tt> attributes.</p>
<p>The IDL definitions do not fully embody the requirements of the W3C DOM API,
such as the notion of certain objects, such as the return value of
<tt class="xref docutils literal"><span class="pre">getElementsByTagName()</span></tt>, being &#8220;live&#8221;.  The Python DOM API does not require
implementations to enforce such requirements.</p>
</div>
</div>
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            <h3><a href="../contents.html">Table Of Contents</a></h3>
            <ul>
<li><a class="reference external" href="">20.6. <tt class="docutils literal"><span class="pre">xml.dom</span></tt> &#8212; The Document Object Model API</a><ul>
<li><a class="reference external" href="#module-contents">20.6.1. Module Contents</a></li>
<li><a class="reference external" href="#objects-in-the-dom">20.6.2. Objects in the DOM</a><ul>
<li><a class="reference external" href="#domimplementation-objects">20.6.2.1. DOMImplementation Objects</a></li>
<li><a class="reference external" href="#node-objects">20.6.2.2. Node Objects</a></li>
<li><a class="reference external" href="#nodelist-objects">20.6.2.3. NodeList Objects</a></li>
<li><a class="reference external" href="#documenttype-objects">20.6.2.4. DocumentType Objects</a></li>
<li><a class="reference external" href="#document-objects">20.6.2.5. Document Objects</a></li>
<li><a class="reference external" href="#element-objects">20.6.2.6. Element Objects</a></li>
<li><a class="reference external" href="#attr-objects">20.6.2.7. Attr Objects</a></li>
<li><a class="reference external" href="#namednodemap-objects">20.6.2.8. NamedNodeMap Objects</a></li>
<li><a class="reference external" href="#comment-objects">20.6.2.9. Comment Objects</a></li>
<li><a class="reference external" href="#text-and-cdatasection-objects">20.6.2.10. Text and CDATASection Objects</a></li>
<li><a class="reference external" href="#processinginstruction-objects">20.6.2.11. ProcessingInstruction Objects</a></li>
<li><a class="reference external" href="#exceptions">20.6.2.12. Exceptions</a></li>
</ul>
</li>
<li><a class="reference external" href="#conformance">20.6.3. Conformance</a><ul>
<li><a class="reference external" href="#type-mapping">20.6.3.1. Type Mapping</a></li>
<li><a class="reference external" href="#accessor-methods">20.6.3.2. Accessor Methods</a></li>
</ul>
</li>
</ul>
</li>
</ul>

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